In this post we will discuss DNS Doctoring on Cisco ASA firewalls. This is a useful feature and although it’s very simple to configure, not many people know about it. DNS Doctoring is helpful in the following situation: Assume you have a Web Server connected to a DMZ zone on a Cisco ASA firewall and […]
Cisco Switch EtherChannel Configuration – LACP – PAgP
In this article we will describe how to configure both LACP and PAgP EtherChannels on Cisco switches. An EtherChannel is a Link Aggregation technology whereby two switches are connected together with multiple interfaces which are bundled together to form a single logical interface (“Port-Channel”) therefore increasing bandwidth between the switches. EtherChannel Use-Case The diagram below […]
Cisco ASA 5506-X Configuration Tutorial – Guide
Throughout my professional career in networking I was lucky to work with all Cisco firewall models and therefore I have experienced the “evolution” of every firewall product developed by Cisco. For the SMB/SOHO market, Cisco’s initial offering was the PIX 501, followed by the successful Cisco ASA 5505. The latter came to an End-of-Sale in […]
ExtraBacon Cisco ASA Vulnerability
A new serious vulnerability was discovered on Cisco ASA devices, called “EXTRABACON”, and was recently patched by Cisco by releasing several software updates for the device. You need to carefully read the following security advisory (CVE-2016-6366) from Cisco and patch your devices as soon as possible. At the end of the article above there is […]
Cisco ASA Firewall Commands – Cheat Sheet
In this post I have gathered the most useful Cisco ASA Firewall Commands and created a Cheat Sheet list that you can download also as PDF at the end of the article. I have been working with Cisco firewalls since 2000 where we had the legacy PIX models before the introduction of the ASA 5500 […]
What will happen to Internet Traffic by 2020 – Some Statistics
On June 7, 2016, Cisco released the “Cisco Visual Networking Index™ (VNI) Complete Forecast for 2015 to 2020” where several notable internet traffic statistics are predicted by the networking giant. I have summarized the forecast document and presenting you below the most important stats and predictions about Internet traffic, Internet usage etc: Global IP traffic […]
Cisco Router Configuration Commands – CLI Cheat Sheet
In a previous post, I have published a Cisco Switch Commands Cheat Sheet tutorial. Since these kinds of posts are useful as a reference for many people, I have decided to create also a Cisco Router Commands Cheat Sheet with the most useful and the most frequently used Command Line Interface (CLI) configuration commands for […]
Cisco Switch Commands Cheat Sheet (CLI)
Cisco switches can be used as plug-and-play devices out of the box but they also offer an enormous amount of features. Although the main purpose of the switch is to provide inter-connectivity in Layer 2 for the connected devices of the network, there are myriad features and functionalities that can be configured on Cisco Switches. […]
Cisco Switch Port Security Configuration and Best Practices
Introduction One of the best practices in network security is to try and stop security threats from the entry-point of a LAN network. This means that the switch can play an important role in network security since it’s the entry-point of the network. For example, port- security on Cisco switches can be used to stop […]
Converting an Autonomous Access Point to Lightweight AP
Introduction In my previous article, I talked about basic configuration of a Cisco WLC controller. In that post I stated that there are two wireless architectures, Distributed and Centralized. Distributed architectures incorporate Access Points (APs) that are standalone without any central management. The APs in distributed architecture are also called Autonomous Access Points. On the […]
Cisco Wireless LAN Controller Basic Configuration
In this article we will go through a basic step-by-step configuration of a Cisco Wireless LAN Controller. Before going forward, let’s first see some basics about the product and the wlan technology from Cisco: Introduction Cisco introduced two types of Wireless architectures in its WiFi portfolio: Distributed Architecture. Centralized Architecture. Distributed WiFi Architecture: In Distributed […]
10 Free Cisco Video Training Courses
Back in the day when I started studying for my Cisco certifications (around 17 years ago), I remember that the only options available to study for the exams were the following: CiscoPress Books (plus some other authors): I remember that if you could sit down and study the whole 600-pages official Cisco Press book for […]
Cisco CCNA Salary
In this article I have done some research to find out the average CCNA salary (in the USA) which is an important factor to consider if you are interested to pursue such a professional certification to advance your career. Before going after any professional certification, it is a good idea to research the demand in […]